Erratum to: Overview on Solid 4He and the Issue of Supersolidity

In the original article, the text in Sect. 6.1.9 on page 350 has a misplaced reference in addition to a sentence missing. The two sentences “On the basis of many-body theory starting from localized orbitals for 4He, Anderson has argued that necessarily the ground state of boson particles has defects. This work is summarized in a paper in these special issues [212]” should be replaced by the following: “On the basis of many-body theory starting from localized orbitals for 4He, Anderson has argued that necessarily the ground state of boson particles has defects [234, 296]. In a paper in these special issues [212], Anderson argues that, even in absence of defects, exchange processes of bosons in the solid are enough to establish a local phase so that the system has vortex-like excitations. From an analysis of the Boson Hubbard model, he argues [297, 212] that this system at the lowest temperatures is in a novel state of matter that has superflow, but not ODLRO, and he conjectures that a similar state is present in solid 4He with vortex excitations essentially decoupled from phonons. This possibility warrants further deep theoretical investigations”.